Absolutely worth having some kind of temp control, not just for initial activation, but for routine fermentation and proofing. Small temp differences over a day or two can have a major impact on the behavior of the culture.

I used to have an oven that had no light, so I built a styrofoam one. Works great. I now have an upgraded oven with a light, so I usually just turn the light on and proof in the oven. If the oven's in use I still have the stryofoam proofing box though..

I'm in the process of trying to make a proof box. The cord I have is from a lamp kit. It has a smooth and a ridged wire.

However, the dimmer switch I have is a 3 way dimmer. It has 2 red wires, 1 black, and 1 green.

I'm just not sure what all I need to connect in order to make the dimmer function as a dimmer and not simply a light. I feel like I've tried many combinations and while many will turn the light on, none will actually allow it to dim.